The ACTS project OPEN aims at the study of the feasibility of an Optical Pan-European overlay Network (OPEN), interconnecting major European cities by means of a mesh of high-capacity optical fibre links cross-connected through transparent photonic nodes. The network is built on an existing fibre infrastructure, and offers an upgradable capacity. The scope of OPEN addresses the transport in the optical transmission medium layer and the optical path sub-layer. The potential capacity of each fibre link will be upgradable at least up to 40 Gbit/s, each channel supporting STM-16 SDH or higher data-rate transport service. The proposed approach relies on the extensive use of WDM for both transmission and routing purposes, but the interfacing with high-speed trunks carrying optical time-division multiplexed (OTDM) channels is considered as well. The goal of the project is to assess by modelling, laboratory experiments, and field implementation of a photonic network prototype, the feasibility of the OPEN concept.
Definition of the general specifications of an optimised pan-European network
Evaluation of the physical layer limitations in the OPEN network
Fabrication and packaging of state-of-the-art all-optical functional modules for the OPEN laboratory demonstrations and field trials
Laboratory experiments on Nx2.5 and Nx10 Gbit/s WDM transmission and routing to validate the OPEN concept and demonstrate its upgradability
Implementation of an OTDM/WDM transmultiplexer
Setting up a multiwavelength all-optical cross-connect to be implemented on both field trial infrastructures
Demonstration of long-distance multi-wavelength transmission and routing including network protection, and evaluation of the exploitation limits of optical transparency on two cross-border field trials: one between Norway and Denmark, and the other between France and Belgium
The project work is expected to have an important impact on the build-up of the ACTS Consensus on optically-routed pan-European networks and provide useful inputs to the standardisation bodies. The OPEN field trials would show the feasibility at the pan-European network level of transparent transport service at up to STM-16 level. The work within the Consortium will also give general specifications of an optimised network, and help evaluate the physical limitations pertaining to WDM transmission and routing, thus providing guidelines for the design of a pan-European network.
Main contributions to the programme objectives:
Design of a satellite and cable High Definition Audio Visual Services distribution network for permanent and temporary exhibition sites such as cinemas, community and cultural centres and universities.
Contribution to the programme
Demonstration of transmission of High Definition Audio Visual Services via Satellite and Cable as possible services for the Information Society
The main aspects of the project workplan are:
the specification and dimensioning of the network and of the network elements on the basis of realistic traffic assumptions and generic network requirements,
the fabrication and delivery of packaged prototype functional blocks based on the most advanced optoelectronic devices such as wavelength encoders and multiwavelength space routers (in collaboration with ACTS project KEOPS), flat-gain optical fibre amplifiers, high-speed transmitters, and dispersion compensators,
the implementation and operation of a prototype 4x4 multiwavelength cross-connect, featuring all-optical space and wavelength routing stages and allowing for transparent routing without electrical regeneration of signals, in two cross-border field trials, one between Norway and Denmark, the second between France and Belgium, aimed at demonstrating the transparent transport and routing of STM-16 optical data streams,
the laboratory demonstration of the upgradability of the basic routing blocks towards 10 Gbit/s per channel operation and of the feasibility of an OTDM/WDM optical interfacing block.
The technical workplan is divided into five workpackages:
WP0 on project management and liaison with the ACTS horizontal projects,
WP1 on network aspects, including network requirements, network modelling, specification of OPEN and of the field trials,
WP2 on functional modules, including the fabrication and packaging of the key optoelectronic modules required in laboratory and field experiments,
WP3 on system evaluation, including assessment of 10 Gbit/s transmission and routing experiments, realisation of an OTDM/WDM interface,
WP4 on preparation and exploitation of field trials.
Summary of trials
Two field trials will be prepared, carried out and further exploited by experimental investigations in the laboratory. The two field trials will address different cases of implementation of a transparent overlay network using existing infrastructures:
first a wavelength routing demonstration will be carried out on a mixed G.652 - G.653 fibre infrastructure linking Oslo, in Norway, with two nodes, Hjørring (transit node) and Thisted (terminal node), in Denmark. This experiment will be focused on the demonstration of long distance transmission and routing, involving both long amplifier spacings and potential FWM effects. The existence of two alternate routes from Norway to Thisted will allow protection demonstration
second, an experimental evaluation of the limits of exploitation of the optical transparency will be carried out using one G.652 fibre infrastructure linking Paris and Brussels, and allowing for the investigation of node cascadability (up to four conversions) and fast restoration issues.
Three types of experiments will be undertaken:
end-to-end multiwavelength transmission and routing demonstration,
evaluation of transparency limits.
Both field trials will be sequentially equipped with the same multiwavelength optical cross-connection node, and optical amplifiers and dispersion compensating fibre spools taken from the same common set, built by the consortium, and support the transport of STM-16 data streams.
Selection of basic requirements from which the overall physical dimensioning of the network and its elements will be derived,
assembly of a field transportable cross-connect prototype, almost entirely made of advanced optoelectronic functional blocks from the laboratory,
assessment of the feasibility of the OPEN concept by means of sensible experiments carried out on existing fibre infrastructure offering long distance optical routes but limited degree of freedom in terms of network topology,
implementation of an all-optical interface between WDM and OTDM systems.
Funding SchemeCSC - Cost-sharing contracts